A touch screen, which is so called as touch control panel, is a sensing-type liquid crystal display apparatus which could accept input signals made by touch ends such as finger touching. When a graphic button on the screen is touched, a touch feedback system on the screen determines a location of the touch action in accordance with a preset scan method, and further determines the graphic button being touched so as to determine a type of an instruction. Compared with the conventional mechanical button panel, the touch screen is more convenient and therefore is applied widely.
A projected capacitive touch screen, which uses the touch control technique comprising self-capacitive touch technique and mutual-capacitive touch technique wherein a capacitance variation is generated when the finger is closing to the capacitive touch control panel, is one of the commonly used touch screens. It also comprises out-cell touch technique and embedded touch technique, wherein the embedded touch technique further comprises in-cell touch control technique and on-cell touch control technique. As the touch screen technique being developed, the in-cell touch control technique gradually becomes a main technique of the touch screen of middle or small size. By integrating a touch control electrode into the cell and processing an image signal and a touch screen signal separately by a same one control IC utilizing time division multiple access theory, a depth and a weight of a touch control display panel can be reduced for a certain degree.
Wherein, the in-cell touch control technique nowadays comprises a hybrid in-cell touch control technique. Since a part of the touch control electrodes are integrated into a common electrode of the array substrate in the hybrid in-cell touch control technique, the conducting lines coupled to the same electrode are relatively increased, and a space of the display screen and a space for expanding the signal lines are limited, the lengths of the conductors 103 for coupling the pixel electrodes and the common electrode of the array substrate are therefore different as shown in FIG. 1, i.e. the resistance of one with longer distance is different from the resistance of one with shorter distance, so that a voltage value at each common electrode terminal of the array substrate is different from others, the Vcom shift occurs, and finally the voltage values applying on the liquid crystal pixels are different and the problem of image non-uniformity occurs.